Online purchasing is typically carried out by selecting items from an online catalog of items and adding them to an online shopping cart. Once all required items have been added to the shopping cart a payment method is selected and the order is submitted. The items may then be shipped to the customer's address.
Mail-order purchasing is typically carried out by selecting items from a pre-printed catalog delivered by mail, filling in an associated order form and submitting the order by mail, or submitting the order by telephone.